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Damage smear method for rock failure process analysis

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Journal of Rock Mechanics and geotechnical Engineering 2019年第6期11卷 1151-1165页

作者： g.li x.F.Cheng H.Pu C.A.Tang state key laboratory of coastal and offshore engineering dalian university of technologydalian116024china state key laboratory for geomechanics and deep underground engineering china university of mining and technologyxuzhou221116china ocean engineering joint research center of dut-uwa dalian university of technologydalian116024china

Damage smear method(DSM)is adopted to study trans-scale progressive rock failure process,based on statistical meso-damage model and finite element *** statistical approach is utilized to reflect the mesoscopic rock *** constitutive law of representative volume element(RVE)is established according to continuum damage mechanics in which double-damage criterion is *** damage evolution and accumulation of RVEs are used to reveal the macroscopic rock failure *** single RVE will be represented by one unique *** initiation,propagation and coalescence of meso-to macro-cracks are captured by smearing failed *** above ideas are formulated into the framework of the DSM and programed into self-developed rock failure process analysis(RFPA)*** laboratory-scale ex.mples are conducted and the well-known engineering-scale tests,*** Energy of Canada limited’s(AECL’s)Underground Research Laboratory(URL)tests,are used for *** shows that the simulation results match with other ex.erimental results and field observations.

关键词： Failure process Smear method Meso-damage Finite element method (FEM) Rock failure process analysis (RFPA)

Bioelectronic medicine in modulation of cortical spreading depolarization and beyond

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Neural Regeneration Research 2025年第2期20卷 481-482页

作者： Khaled Alok Timothy g.White Chunyan li Department of Neurosurgery Donald and Barbara Zucker School of Medicine at Hofstra/NorthwellHempsteadNYUSA Translational Brain Research Laboratory The Feinstein Institutes for Medical ResearchManhassetNYUSA

Bioelectronic interventions,specifically trigeminal nerve st imulat ion(TNS),have attracted considerable attention in conditions where cortical spreading depolarizations(CSDs)accompanied by compromised cerebral perfusion may ex.cerbate neurological *** pharmacological interventions have demonstrated initial potential in addressing CSDs,a standardized treatment approach has not yet been *** objective of this perspective is to ex.lore emerging bioelectronic methodologies for addressing CSDs,particularly emphasizing TNS,and to underscore TNS’s capacity to enhance neurovascular coupling and cerebral perfusion.

关键词： cerebral perfusion electronic

A semi-analytical approach for calculating the equilibrium structure and radial breathing mode frequency of single-walled carbon nanotubes

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Acta Mechanica Sinica 2016年第6期32卷 1075-1087页

作者： J.gong L.Thompson g.li Department of Mechanical Engineering Clemson University

A semi-analytical model for determining the equilibrium configuration and the radial breathing mode (RBM) frequency of single-wall carbon nanotubes (CNTs) is presented. By taking advantage of the symmetry characteristics, a CNT structure is represented by five independent variables. A line search optimization procedure is employed to determine the equilibrium values of these variables by minimizing the potential energy. With the equilibrium configuration obtained, the semi-analytical model enables an efficient calculation of the RBM frequency of the CNTs. The radius and radial breathing mode frequency results obtained from the semi-analytical approach are compared with those from molecular dynamics (MD) and ab initio calculations. The results demonstrate that the semi-analytical approach offers an efficient and accurate way to determine the equilibrium structure and radial breathing mode frequency of CNTs.

关键词： Carbon nanotubes Equilibrium structure Radial breathing mode frequency

Improvement of elevated-temperature strength and recrystallization resistance via Mn-containing dispersoid strengthening in Al-Mg-Si 6082 alloys

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Journal of Materials Science & Technology 2020年第4期39卷 135-143页

作者： Chen li Kun liu x.-grant Chen Department of Applied Science University of Québec at ChicoutimiChicoutimiQC G7H 2B1Canada

The precipitation behavior of Mn-containing dispersoids in Al-Mg-Si 6082 alloys with different Mn contents(0,0.5 and 1.0 wt%)during various heat treatments(300–500℃)was *** effects of dispersoids on elevated-temperature strength and recrystallization resistance during hot-rolling and post-rolling annealing were *** results showed that the dispersoids in the Mn-containing alloys(0.5 and 1.0%)began to precipitate at 350℃and reached the optimum conditions after 2–4 h at 400℃.However,the dispersoids coarsened with increasing holding time at temperatures above450℃.After the peak precipitation treatment at 400℃for 2 h,the yield strength at 300℃increased from 28 MPa(base alloy free of Mn)to 55 MPa(alloy with 0.5%Mn)and 70 MPa(alloy with 1%Mn),respectively,demonstrating a significant dispersoid strengthening effect at elevated *** addition,the dispersoids were thermally stable at 300℃for up to 1000 h holding owing to its relative high precipitation temperature(350–400℃),leading to the superior constant mechanical performance at elevated temperature during the long service *** hot rolling and post-rolling annealing,the presence of a large amount of dispersoids results in the higher Zener drag PZcompared with base alloy and then significantly improved the recrystallization *** alloy containing 0.5%Mn ex.ibited the highest recrystallization resistance among three ex.erimental alloys studied during the post-rolling process,likely resulted from the lower coarsening rate of dispersoids and the lower dispersoids free zone.

关键词： Al-Mg-Si 6082 alloy Mn addition Dispersoid precipitation Elevated-temperature strength Recrystallization resistance

Double heterogeneous structures induced ex.ellent strength-ductility synergy in Ni_(40)Co_(30)Cr_(20)Al_(5)Ti_(5) medium-entropy alloy

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Journal of Materials Science & Technology 2024年第14期181卷 176-188页

作者： A.x.li x.S.liu R.li S.B.Yu M.H.Jiang J.S.Zhang C.N.Che D.Huang P.F.Yu g.li State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China

The application of single-phase face-centered cubic(FCC)medium entropy alloys(MEAs)in the engi-neering industry is often hindered by the challenge of insufficient *** this study,a novel non-equiatomic ratio Ni_(40)Co_(30)Cr_(20)Al_(5)Ti_(5)MEA was successfully *** the well-designed mechan-ical heat treatment processing,we introduced a heterogeneous grain structure comprising 67.4%fine grain and 32.6%coarse ***,heterogeneous size L12 phases consisting of 18.7%submicron precip-itates and 11.7%nano-sized precipitates,were incorporated into the *** tests conducted at room temperature revealed that the double heterogeneous structure alloy demonstrated remarkable strength–ductility *** ex.ibited a yield strength of 1200 MPa,an ultimate tensile strength of 1560 MPa and a total elongation of 33.6%.The ex.eptional strength of the alloy can be primarily attributed to heteroge-neous deformation induced strengthening,grain boundary strengthening and precipitation *** ex.ellent ductility is mainly attributed to the high-density stacking faults and Lomer–Cottrell *** study not only contributes to the clarification of the strengthening and deformation mechanism of double heterogeneous structure alloys but also provides an effective strategy for the development of high-performance alloys with high strength and ductility.

关键词： Medium entropy alloy Double heterogeneous structure HDI strengthening Remarkable tensile properties

Constraints on holographic QCD phase transitions from PTA observations

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 71-78页

作者： Song He li li Sai Wang Shao-Jiang Wang Center for Theoretical Physics and College of Physics Jilin University School of Physical Science and Technology Ningbo University Max.Planck Institute for gravitational Physics (Albert Einstein Institute) CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUniversity of Chinese Academy of Sciences (UCAS) School of Physical Sciences University of Chinese Academy of Sciences (UCAS) Theoretical Physics Division Institute of High Energy Physics Chinese Academy of Sciences

The underlying physics of QCD phase transition in the early Universe remains largely unknown due to its strong-coupling nature during the quark-gluon plasma/hadron gas transition, yet a holographic model has been proposed to quantitatively fit the lattice QCD data while with its duration of the first-order phase transition(FoPT) left undetermined. At specific baryon chemical potential, the first-order QCD phase transition agrees with the observational constraint of baryon asymmetry. It, therefore, provides a scenario for phase transition gravitational waves(gWs) within the standard model of particle physics. If these background gWs could contribute dominantly to the recently claimed common-spectrum red noise from pulsar timing array(PTA) observations, the duration of this FoPT can be well constrained, and the associated primordial black holes are still allowed by current observations.

关键词： pulsar timing array QCD phase transition gravitational waves primordial black holes

Cell polarization in ischemic stroke: molecular mechanisms and advances

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Neural Regeneration Research 2025年第3期20卷 632-645页

作者： Yuanwei li x.aox.ao x. x.an Wu Jiarui li Shiling Chen Danyang Chen gaigai li Zhouping Tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate ex.essive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each ex.ibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the contex. of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complex.ty of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

关键词： astrocyte polarization immune regulation inflammation ischemic injury microglia polarization neutrophil polarization signaling pathways stroke

A note on hydrodynamics from dissipative particle dynamics

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Applied Mathematics and Mechanics(English Edition) 2018年第1期39卷 63-82页

作者： x. BIAN Z. li N.A. ADAMS Department of Mechanical Engineering Technical University of Munich Munchen 85748 Germany Division of Applied Mathematics Brown University Rhode Island 02912 U. S. A.

We calculate current correlation functions （CCFs） of dissipative particle dy- namics （DPD） and compare them with results of molecular dynamics （MD） and solutions of linearized hydrodynamic equations. In particular, we consider three versions of DPD, the empirical/classical DPD, coarse-grained （Cg） DPD with radial-direction interactions only and full （radial, transversal, and rotational） interactions between particles. To fa- cilitate quantitative discussions, we consider specifically a star-polymer melt system at a moderate density. For bonded molecules, it is straightforward to define the Cg variables and to further derive Cg force fields for DPD within the framework of the Mori-Zwanzig formalism. For both transversal and longitudinal current correlation functions （TCCFs and LCCFs）, we observe that results of MD, DPD, and hydrodynamic solutions agree with each other at the continuum limit. Below the continuum limit to certain length scales, results of MD deviate significantly from hydrodynamic solutions, whereas results of both empirical and Cg DPD resemble those of MD. This indicates that the DPD method with Markovian force laws possibly has a larger applicability than the continuum description of a Newtonian fluid. This is worth being ex.lored further to represent gen- eralized hydrodynamics.

关键词： dissipative particle dynamics (DPD) fluctuating hydrodynamics molec-ular dynamics (MD) coarse-graining Mori-Zwanzig projection

Design of a cationic accelerator enabling ultrafast ion diffusion kinetics in aqueous zinc-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 377-384页

作者： Yawei x.ao Qianqian gu Haoyu li Mengyao li Yude Wang National Center for International Research on Photoelectric and Energy Materials School of Materials and Energy Yunnan University Key Laboratory of Ministry of Education for Advanced Materials in Tropical Island Resources School of Chemistry and Chemical Engineering Hainan University College of Chemical Engineering Fuzhou University Yunnan Key Laboratory of Carbon Neutrality and green Low-carbon Technologies Yunnan University

Aqueous zinc-ion batteries are highly favored for grid-level energy storage owing to their low cost and high safety,but their practical application is limited by slow ion *** address this,a strategy has been developed to create a cation-accelerating electric field on the surface of the cathode to achieve ultrafast Zn2+diffusion *** employing electrodeposition to coat MoS2on the surface of BaV6O16·3H2O nanowires,the directional built-in electric field generated at the heterointerface acts as a cation accelerator,continuously accelerating Zn2+diffusion into the active *** optimized Zn2+diffusion coefficient in CC@BaV-6O16·3H2O@MoS2(7.5×10～8cm2s-1) surpasses that of most reported V-based ***,MoS2serving as a cathodic armor ex.ends the cycling.life of the Zn-CC@BaV6O16·3H2O@MoS2full batteries to over 10000 *** work provides valuable insights into optimizing ion diffusion kinetics for high-performance energy storage devices.

关键词： Internal electric field Cationic accelerator Ion diffusion kinetics Cathode modification strategy Aqueous zinc ion battery